Abstract The purpose of the Lipidomics Shared Resource Core (LSR Core) in the PPG is to provide intellectual and physical resources (particularly state-of-the-art mass spectrometry analysis of sphingolipids and flux analysis) to enhance our understanding of the role of bioactive lipids in cancer biology with the goal to discover future drugs. The diversity of bioactive lipids and their interconnected metabolism generates a network of pathways regulating intra- and inter-cellular signaling and function. Dysfunctions in these pathways contribute to the pathobiology of cancer progression and metastasis, the study of which is the main goal for the four experimental projects in this PPG. The vast diversity in sphingolipids with non-redundant, but often opposite functions, has resulted in a necessity for the development of new protocols and analytical methods for their identification and quantification. Appreciation for the depth of complexity involved in sphingolipid metabolism and signaling has recently expanded since (i) same species of sphingolipids could act differently depending on the subcellular compartment and (ii) variations in the acyl chain length or saturation status could lead to specific biological responses. These two new considerations exponentially increase the complexity on sphingolipid studies, and they have not been able to be interrogated until now. The LSR Core was created based on unique expertise of the key personnel in lipid chemistry, analysis, and metabolism, and it has evolved into a key Core for the program project grant (PPG) entitled Sphingolipids in Cancer Biology and Therapeutics. Furthermore, this Core has developed into an institutional, national, and international resource in the emerging fields of lipidomics and lipid chemical biology. Core services include: 1) qualitative and quantitative analysis of lipid components from different biological materials (cells, tissue, and biological fluids), primarily employing high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) technology?the Core currently provides quantitative analysis of more than 300 distinct lipid molecular species at a basic metabolomic level; 2) development of biochemical tools to study lipid metabolism (e.g., Sphingoproteomics, Sphingolipid Flux Analysis utilizing a Pulse-Chase of non-natural C17-sphingolipids, functionalized and fluorescent ceramides, site-specific radioactive sphingolipids); and 3) assisting PPG investigators in experimental design, selection of appropriate methods, and interpretation of analytical results. The LSR Core has been instrumental to the success of the PPG investigators over the past 16 years by providing them with unique capabilities and critical results that will continue to ensure the successful progress of this PPG.